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| pimpom... |
 Posted: Fri Nov 06, 2009 1:17 pm |
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Guest
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Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for is a
type that has become popular enough to be regarded almost as an
industry standard and be available anywhere (and at a low price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential |
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| mpm... |
| Posted: Fri Nov 06, 2009 1:17 pm |
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On Nov 6, 1:05 pm, "pimpom" <pim... at (no spam) invalid.com> wrote:
[quote]Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for is a
type that has become popular enough to be regarded almost as an
industry standard and be available anywhere (and at a low price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
[/quote]
I like the National Semi LM2575T series (TO-220 package).
Easy to use, comes in fixed and adjustable varieties, readily
available.
Low frequency switcher.
But there may be better choices out there |
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| petrus bitbyter... |
| Posted: Fri Nov 06, 2009 1:34 pm |
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Guest
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"pimpom" <pimpom at (no spam) invalid.com> schreef in bericht
news:hd1ohb$l0r$1 at (no spam) news.albasani.net...
[quote]Can you please suggest one or more ICs for general use as a step-down
switching voltage regulator? This is for general stock to be used as
needed for a variety of projects. There's a plethora of such devices out
there, but what I'm looking for is a type that has become popular enough
to be regarded almost as an industry standard and be available anywhere
(and at a low price), in much the same way as the linear 78xx series and
the LM317. Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
[/quote]
Last time I needed such a thing I found the MC34063. Looks like to fit your
requirements pretty well.
petrus bitbyter |
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| John Devereux... |
| Posted: Fri Nov 06, 2009 2:05 pm |
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Guest
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"pimpom" <pimpom at (no spam) invalid.com> writes:
[quote]Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for is a
type that has become popular enough to be regarded almost as an
industry standard and be available anywhere (and at a low price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
[/quote]
Most ubiquitous and ridiculously cheap MC34063A and copies, but it is
looking a bit long in the tooth. It's slow and transistor output. So you
will need larger inductors and capacitors, and dissapate more heat, than
more modern devices.
It is frustrating that there don't seem to be any newer parts anywhere
near the price.
--
John Devereux |
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| pimpom... |
| Posted: Fri Nov 06, 2009 2:18 pm |
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Guest
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mpm wrote:
[quote]On Nov 6, 1:05 pm, "pimpom" <pim... at (no spam) invalid.com> wrote:
Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general
stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for
is a
type that has become popular enough to be regarded almost as
an
industry standard and be available anywhere (and at a low
price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
I like the National Semi LM2575T series (TO-220 package).
Easy to use, comes in fixed and adjustable varieties, readily
available.
Low frequency switcher.
But there may be better choices out there
[/quote]
Thanks. I'd already looked at the LM25575 but the external
component count is a bit more than I'd like, though it seems to
have regulation and efficiency than the LM2575. I think I've seen
the 2575 used more than once before, but a browse of the NatSem
site didn't bring it up immediately, so it didn't come to mind
until you suggested it. Looks like it will do nicely. Thanks
again. |
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| pimpom... |
| Posted: Fri Nov 06, 2009 2:19 pm |
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petrus bitbyter wrote:
[quote]"pimpom" <pimpom at (no spam) invalid.com> schreef in bericht
news:hd1ohb$l0r$1 at (no spam) news.albasani.net...
Can you please suggest one or more ICs for general use as a
step-down
switching voltage regulator? This is for general stock to be
used as
needed for a variety of projects. There's a plethora of such
devices
out there, but what I'm looking for is a type that has become
popular enough to be regarded almost as an industry standard
and be
available anywhere (and at a low price), in much the same way
as the
linear 78xx series and the LM317. Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
Last time I needed such a thing I found the MC34063. Looks like
to
fit your requirements pretty well.
petrus bitbyter
[/quote]
Thanks. I'd already saved the datasheet of the MC34063. If it's
widely available, it's a good candidate. |
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| pimpom... |
| Posted: Fri Nov 06, 2009 2:39 pm |
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Guest
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John Devereux wrote:
[quote]"pimpom" <pimpom at (no spam) invalid.com> writes:
Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general
stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for
is a
type that has become popular enough to be regarded almost as
an
industry standard and be available anywhere (and at a low
price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
Most ubiquitous and ridiculously cheap MC34063A and copies, but
it is
looking a bit long in the tooth. It's slow and transistor
output. So
you will need larger inductors and capacitors, and dissapate
more
heat, than more modern devices.
It is frustrating that there don't seem to be any newer parts
anywhere
near the price.
[/quote]
Thanks. By transistor output, I take it you mean bipolar. The
datasheet I have of the MC34063A is by ON Semi. It gives only a
limited amount of info about the efficiency and dissipation.
Maybe I should download one from another manufacturer. |
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| John Larkin... |
| Posted: Fri Nov 06, 2009 3:06 pm |
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Guest
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On Fri, 6 Nov 2009 23:35:31 +0530, "pimpom" <pimpom at (no spam) invalid.com>
wrote:
[quote]Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for is a
type that has become popular enough to be regarded almost as an
industry standard and be available anywhere (and at a low price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
[/quote]
LM2672 is cute, 1 amp in an SO-8, 260 KHz.
Lately we've been using a lot of LTM8023s, which is a switcher with
internal Ls and Cs and everything. A bit expensive, but very simple
and very clean. It's sort of a BGA package.
John |
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| Spehro Pefhany... |
| Posted: Fri Nov 06, 2009 3:40 pm |
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On Fri, 06 Nov 2009 19:05:28 +0000, John Devereux
<john at (no spam) devereux.me.uk> wrote:
[quote]"pimpom" <pimpom at (no spam) invalid.com> writes:
Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for is a
type that has become popular enough to be regarded almost as an
industry standard and be available anywhere (and at a low price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
Most ubiquitous and ridiculously cheap MC34063A and copies, but it is
looking a bit long in the tooth. It's slow and transistor output. So you
will need larger inductors and capacitors, and dissapate more heat, than
more modern devices.
It is frustrating that there don't seem to be any newer parts anywhere
near the price.
[/quote]
If you have that kind of requirement, there are definitely some
offshore-only parts that are probably near the price (probably lower
maximum input voltage). Try tearing apart some consumer goods. Also
some of the NS switchers have been cloned. |
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| who where... |
| Posted: Fri Nov 06, 2009 6:12 pm |
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Guest
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On Fri, 06 Nov 2009 12:06:01 -0800, John Larkin
<jjlarkin at (no spam) highNOTlandTHIStechnologyPART.com> wrote:
[quote]On Fri, 6 Nov 2009 23:35:31 +0530, "pimpom" <pimpom at (no spam) invalid.com
wrote:
Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for is a
type that has become popular enough to be regarded almost as an
industry standard and be available anywhere (and at a low price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
LM2672 is cute, 1 amp in an SO-8, 260 KHz.
Lately we've been using a lot of LTM8023s, which is a switcher with
internal Ls and Cs and everything. A bit expensive, but very simple
and very clean. It's sort of a BGA package.
[/quote]
John (or anyone else here), have you looked at the RECOM R-78 series
"TO220-style" integrated switchers? They won't fit a "low cost"
category of course. I'd be very interested in comments from anyone
who has used them. (I have eyed them off for a project in the past
but wound up laying out an MC34063 solution.) |
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| Raveninghorde... |
| Posted: Fri Nov 06, 2009 6:34 pm |
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On Fri, 06 Nov 2009 19:05:28 +0000, John Devereux
<john at (no spam) devereux.me.uk> wrote:
[quote]"pimpom" <pimpom at (no spam) invalid.com> writes:
Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for is a
type that has become popular enough to be regarded almost as an
industry standard and be available anywhere (and at a low price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
Most ubiquitous and ridiculously cheap MC34063A and copies, but it is
looking a bit long in the tooth. It's slow and transistor output. So you
will need larger inductors and capacitors, and dissapate more heat, than
more modern devices.
It is frustrating that there don't seem to be any newer parts anywhere
near the price.
[/quote]
I'm using an NCP3063 which is a higher speed upgrade on a current
project. It's useful where you need buck or boost.
My unit has low power 5V buck and a 24V boost to power the sepic
circuitry as well as USB charger outputs. All bult around the NCP
3063. The MC34063 wasn't good enough on the first prototypes. |
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| John Devereux... |
| Posted: Sat Nov 07, 2009 3:00 am |
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Raveninghorde <raveninghorde at (no spam) invalid> writes:
[quote]On Fri, 06 Nov 2009 19:05:28 +0000, John Devereux
john at (no spam) devereux.me.uk> wrote:
"pimpom" <pimpom at (no spam) invalid.com> writes:
Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for is a
type that has become popular enough to be regarded almost as an
industry standard and be available anywhere (and at a low price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
Most ubiquitous and ridiculously cheap MC34063A and copies, but it is
looking a bit long in the tooth. It's slow and transistor output. So you
will need larger inductors and capacitors, and dissapate more heat, than
more modern devices.
It is frustrating that there don't seem to be any newer parts anywhere
near the price.
I'm using an NCP3063 which is a higher speed upgrade on a current
project. It's useful where you need buck or boost.
My unit has low power 5V buck and a 24V boost to power the sepic
circuitry as well as USB charger outputs. All bult around the NCP
3063. The MC34063 wasn't good enough on the first prototypes.
[/quote]
I've used that one too and you're right. Still only 150kHz and bipolar
though. Might be a good fit for the OP.
--
John Devereux |
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| pimpom... |
| Posted: Sat Nov 07, 2009 1:42 pm |
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John Larkin wrote:
[quote]On Fri, 6 Nov 2009 23:35:31 +0530, "pimpom"
pimpom at (no spam) invalid.com
wrote:
Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general
stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for
is a
type that has become popular enough to be regarded almost as
an
industry standard and be available anywhere (and at a low
price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
LM2672 is cute, 1 amp in an SO-8, 260 KHz.
It's cute all right, but not as cheap as I'd like it to be.[/quote]
[quote]Lately we've been using a lot of LTM8023s, which is a switcher
with
internal Ls and Cs and everything. A bit expensive, but very
simple
and very clean. It's sort of a BGA package.
That's real neat but, as you say, way too expensive for the kind[/quote]
of use I have in mind. It's certainly worth keeping in mind for
other purposes where price is not an important factor. |
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| pimpom... |
| Posted: Sat Nov 07, 2009 2:11 pm |
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Raveninghorde wrote:
[quote]On Fri, 06 Nov 2009 19:05:28 +0000, John Devereux
john at (no spam) devereux.me.uk> wrote:
"pimpom" <pimpom at (no spam) invalid.com> writes:
Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general
stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for
is a
type that has become popular enough to be regarded almost as
an
industry standard and be available anywhere (and at a low
price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
Most ubiquitous and ridiculously cheap MC34063A and copies,
but it is
looking a bit long in the tooth. It's slow and transistor
output. So
you will need larger inductors and capacitors, and dissapate
more
heat, than more modern devices.
It is frustrating that there don't seem to be any newer parts
anywhere near the price.
I'm using an NCP3063 which is a higher speed upgrade on a
current
project. It's useful where you need buck or boost.
My unit has low power 5V buck and a 24V boost to power the
sepic
circuitry as well as USB charger outputs. All bult around the
NCP
3063. The MC34063 wasn't good enough on the first prototypes.
[/quote]
The NCP3063 looks like a good trade-off between price and
performance, and the boost option is attracttive. Perhaps a mixed
stock of it and the MC34063 will be a good idea. |
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| pimpom... |
| Posted: Sat Nov 07, 2009 2:17 pm |
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Guest
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who where wrote:
[quote]On Fri, 06 Nov 2009 12:06:01 -0800, John Larkin
jjlarkin at (no spam) highNOTlandTHIStechnologyPART.com> wrote:
On Fri, 6 Nov 2009 23:35:31 +0530, "pimpom"
pimpom at (no spam) invalid.com
wrote:
Can you please suggest one or more ICs for general use as a
step-down switching voltage regulator? This is for general
stock
to be used as needed for a variety of projects. There's a
plethora of such devices out there, but what I'm looking for
is a
type that has become popular enough to be regarded almost as
an
industry standard and be available anywhere (and at a low
price),
in much the same way as the linear 78xx series and the LM317.
Desireable specs would be -
1. Low external component count
2. Max input voltage around 40V
3. Max load current 1A or more
4. Fixed or adjustable output voltage
5. Output voltage range 5-15V or wider
6. Non-SMD if possible, but not essential
LM2672 is cute, 1 amp in an SO-8, 260 KHz.
Lately we've been using a lot of LTM8023s, which is a switcher
with
internal Ls and Cs and everything. A bit expensive, but very
simple
and very clean. It's sort of a BGA package.
John (or anyone else here), have you looked at the RECOM R-78
series
"TO220-style" integrated switchers? They won't fit a "low
cost"
category of course. I'd be very interested in comments from
anyone
who has used them. (I have eyed them off for a project in the
past
but wound up laying out an MC34063 solution.)
[/quote]
The R-78 series would be perfect (~95% efficiency, through-hole
option, no external parts except the inevitable input-output
caps) but I couldn't find indicative prices with a quick search.
I expect they'll be a bit on the high side for my purpose and
also not easily available everywhere. |
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